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301.
Park planning, once at the root of the profession during the nineteenth century, can again provide cities with a means to improve public health through restricting access to automobiles. This intercept study, conducted in New Orleans City Park, found that two-thirds of users support weekend street closures to automobiles. Widespread support (63%) exists even among the 72% of people who arrived by automobile. This study also found measurable stated benefits from restricting car access. For more than 53% of the sample that stated that they would walk more in a car-free zone, respondents noted that they would walk nearly 30?min more per month. These findings suggest that planners and policy-makers have a cost-effective option to improve cities and public health – taming the automobile in urban parks. 相似文献
302.
Co-production of electricity, district heat and industrial heat/process steam (heat and power, CHP) has been applied to a large, national scale, in only a few countries in the world, Denmark, The Netherlands and Finland. In this production method, the waste energy from electricity production is used in two quality levels. First, industrial process steam requirements can be met with this residual energy. Second, the waste energy is used in local district heating networks for households and other buildings in a city. In this integrated production method, a total fuel efficiency of 85% can be achieved. Through the technique of fluidized bed combustion, modern CHP plants can use coal and oil, and in addition, heterogeneous fuels such as biomass, industrial wastes and recycled fuels from households. In this paper, the CHP method is considered in terms of four categories of material and energy flows. For the purpose of considering the potential environmental gains and the difficulties of this production method when applied to integrated waste management and energy production, the four suggested categories are: matter (biomass) (1), nutrients (2), energy (3) and carbon (4). Corporate environmental management inventory tools, decision-making tools, management, organisational and administrative tools as well as information management tools that could be used in CHP-related material and energy flow management are shortly discussed. It is argued that for CHP energy and environmental management, it can be important to adopt an approach to networks of firms, rather than to an individual firm. The presented material and energy flow model may contribute to assessing, planning and implementing of CHP-based waste management and cleaner energy production. 相似文献
303.
PCDD/Fs and PCBs in surface waters and effluent waste streams flowing into New York/New Jersey Harbor were sampled by large volume filtration and solid phase extraction (XAD-2). Passive hexane samplers were employed in sewer trackdown. Extraction media were analyzed for 2,3,7,8 substituted PCDD/Fs and all 209 PCB congeners. The non-Aroclor PCB congener, 3,3′-DiCB, was ubiquitous in the harbor and was found to be associated with pigment manufacture. Knowledge of inadvertent synthesis of non-Aroclor PCBs is not new but its magnitude and the generation of congeners with dioxin-like properties from this process is novel. 相似文献
304.
This study demonstrates the integration of rehabilitation and flood management planning in a steep, boulder-bedded stream
in a coastal urban catchment on the South Island of New Zealand. The Water of Leith, the primary stream flowing through the
city of Dunedin, is used as a case study. The catchment is steep, with a short time of concentration and rapid hydrologic
response, and the lower stream reaches are highly channelized with floodplain encroachment, a high potential for debris flows,
significant flood risks, and severely degraded aquatic habitat. Because the objectives for rehabilitation and flood management
in urban catchments are often conflicting, a number of types of analyses at both the catchment and the reach scales and careful
planning with stakeholder consultation were needed for successful rehabilitation efforts. This included modeling and analysis
of catchment hydrology, fluvial geomorphologic assessment, analysis of water quality and aquatic ecology, hydraulic modeling
and flood risk evaluation, detailed feasibility studies, and preliminary design to optimize multiple rehabilitation and flood
management objectives. The study showed that all of these analyses were needed for integrated rehabilitation and flood management
and that some incremental improvements in stream ecological health, aesthetics, and public recreational opportunities could
be achieved in this challenging environment. These methods should be considered in a range of types of stream rehabilitation
projects. 相似文献
305.
Jinping Ou Qihou Hu Haoran Liu Shiqi Xu Z.huang Wang Xiangguang Ji Xinqi Wang Zhouqing Xie Hui Kang 《环境科学学报(英文版)》2022,34(1):75-83
New particle formation(NPF) events are an increasingly interesting topic in air quality and climate science. In this study, the particle number size distributions, and the frequency of NPF events over Hefei were investigated from November 2018 to February 2019. The proportions of the nucleation mode, Aitken mode, and accumulation mode were 24.59%,53.10%, and 22.30%, respectively, which indicates the presence of abundant ultrafine particles in Hefei. Forty-six NPF events occurred during the obser... 相似文献
306.
Over the past 30 years, urban environmental pollution governance has been increasingly influenced by ideas of New Public Management. However, there is increasing evidence that it is failing in its promise to deliver efficient and effective regulation. The critiques are mounting of risk-based approaches, where regulators are increasingly accountable for the costs (and benefits) of their interventions upon firms.There is a particular lack of research on the role of conduct and practices involved on the ‘front line’ of regulation. This constrains our ability to understand how more efficient effective urban environmental pollution control might develop. This paper focuses on the regulator field officers and business duty holders of environmental compliance, who have direct contact in the processes and administration of regulation. Applying theories of social practice to environmental regulation, the paper provides new insights into compliance and enforcement practices, as these workers seek to prevent pollution, remediate sites and manage waste. The analysis reveals disconnects between expectations of enforcing and managing compliance; and between practices of policing and polluting.Using an ethnographic-informed approach to understand the social practices of regulation has not been attempted in this way before. It reveals new insights into limitations of current approaches to regulation, and indicates interventions that could lead to improved compliance outcomes in a post-New Public Management era in urban pollution governance. 相似文献
307.
金维洙 《中国安全科学学报》2003,13(1):78-80
我国的木材加工企业普遍存在严重的噪声污染 ,极大地损害了工作者的身心健康 ,是迫切需要解决的重要问题。为了控制木工机床的噪声 ,分析和讨论了产生噪声的原因 ,指出切削机构是噪声的主要声源。探讨了降低噪声的途径 ,综合评述了国外木工刀具降噪新技术。在工业发达的国家 ,现代木工刀具的设计与制造均考虑了降噪措施 ,其技术原理集中于控制气流在刀槽或齿槽中涡流产生的空气动力性噪声和防止刀具振动时产生的机械噪声两方面。这些新技术已用于生产中 ,降噪效果明显 ,值得借鉴。笔者强调 ,开发低噪声木工刀具 ,保障劳动者的人体健康 ,是我国木材加工工业文明发展的标志 相似文献
308.
309.
近年来,各部门不断加大农村污染防治和生态保护力度,创新农村环保新机制,农村环保工作取得了积极进展,但是一些新旧环境问题依然存在,并制约着农村的可持续发展。文章对农村环境污染的现状、产生污染的原因及解决对策等方面进行了探讨。 相似文献
310.
龙湾区是温州市的三大城区之一,从20世纪80代以来,随着温州市经济的迅猛发展,人口的增长,龙湾区城市内河水质不断恶化。本文通过对龙湾区内河设置水质监测点,分季度采样分析,对龙湾区内河水质情况进行调查研究,分析各片区的主要污染物,为改善河道水质提供依据。 相似文献